Inflation of water to the soil in the fields of drop irrigation

The article presents theoretical and field experimental data on determining the rates of infiltration and filtration of irrigation water in the soil grounds of the calculated layer in the cotton fields of the Dzharkurgan massif in the Surkhandarya region. Based on the established values of the rates of infiltration of irrigation water, the drip irrigation regime for cotton of the new Sultan variety has been determined, the parameters of the innovative drip irrigation technology have been determined.


Introduction
In the Surkhandarya region of the Republic of Uzbekistan, in recent years, innovative technology for irrigation of agricultural crops has been rapidly introduced; the introduction of innovative irrigation technology is shown in Figure 1 and table [1][2][3].

Materials and Methods
The experimental plot with a drip irrigation area of 60 ha is located on the Dzharkurgan massif. The source of irrigation is the main canal "Amu-Zang", which takes irrigation water from the Amu Darya river. The surface of the experimental plot has a slope of i = 0.003-0.004; the soils are light in terms of mechanical composition, bulk density is 1.1-1.26 t / m 3 , sandy loam, and light loam, not saline, are widespread, the depth of groundwater during the year varies from 2.6-2.8 to 3.1-3.5 m.

Fig. 2. The location of the experimental plot is shown in
The experimental plot is typical for climatic, soil, geological, hydrogeological, hydrological, and economic conditions of the Dzharkurgan irrigation massif; it was selected based on the methods of V.V. Shabanov and E.P. Rudachenko [15][16][17][18].
In the case of drip irrigation, cotton irrigation was carried out through an extensive network of pipelines through special micro-outlets directly to the root zone, maintaining soil moisture throughout the growing season at a level close to the calculated one. At the same time, this created the possibility of a continuous supply of water to plants and nutrients. The estimated drip flow rate was 3.2 -3.6 l/h.
The main methodological provisions are based on theoretical and experimental studies, a broad generalization of the practice of drip irrigation of cotton by the research of TIIIMSKH, NIISSAVKH, NIIIVP, TashSAU, VNIIGIM named after A.N. Kostyakov, Volgograd State Autonomous Institution, Moscow State Agrarian University named after Timiryazeva et al. Field studies were carried out using standard and specially developed methods, the reliability of the results was evaluated by verifying the results of theoretical and field studies [18][19][20][21][22][23][24][25][26].

Results and Discussion
In the widespread introduction of resource-saving irrigation methods and techniques, and with a wise choice of crop irrigation technology, one of the main factors is the soil reclamation conditions of the irrigated massif. In the Surkhandarya region of the Dzharkurgan district, LLC "Surkhon Sifat Textel" Dienov, a branch of the Dzharkurgan array of cotton drip irrigation, we conducted field experimental studies to establish the value of the infiltration and filtration of irrigation water in the soil of the settlement layer. The quality of irrigation, maintaining the soil structure, maintaining the reclamationecological state of the land, the duration of irrigation, the value of the elementary irrigation rate, the number of irrigations of agricultural crops by interconnections.
With all irrigation methods by the rabbits of intra-soil and sub-irrigation, water is supplied to the soil surface and is absorbed into it very quickly, then more slowly. The absorption process is characterized by the depth of soaking and speed, infiltration by which we mean the height of the words of water absorbed into the soil per unit of time. According to A.N. Kostyakov, it changes in time according to: Where t v is the absorption rate at a given point at time t; t is the duration of absorption; 1 v is absorption rate at the end of the first unit of time; t a is exponent, varying from 0.3 to 0.8, depending on the nature of the soil and its initial moisture content.
α is an indicator of the degree of the infiltration curve.
Where v t is infiltration rate at time t, m/h. The average absorption rate over time t is equal to: formula describes the process quite well. The time course of the absorption process depends not only on the nature of the soil and its moisture but also on several other factors: pressure gradients, soil swelling, destruction of soil aggregates, compaction and swimming of pores, colmatization, and closing of cracks, type of soil surface, and the presence of soil or other salts, water temperature. The first stage of the infiltration process -inflation is characterized by water movement in the soil along cracks, large voids, the swaths of the earth swarms, root passages. The hydromechanical solution of the one-dimensional problem of absorbing water into the soil, which allows one to determine the depth of soaking for different points in time, was given by V.V. Vedernikov. The equation obtained by him has the form: Where h is depth of water on the surface of the soil or soil; k H is height of capillary rise; y is wetting depth; f R is filtration coefficient; 1 m is free porosity or coefficient of lack of saturation; t is duration of infiltration.
Over time t, a layer of water is absorbed into the soil: For uniform moistening of the soil over the entire area of the irrigated area, the absorption time must be the same for each point of the dropper, which provides sufficient uniformity of moisture calculated for the depth of the soil.
In logarithmic coordinates, the absorption curve during the infiltration period ) (